CDC's National Immunization Survey:
Methodological Problems Limit Survey's Utility
PEMD-96-16: Published: Sep 19, 1996. Publicly Released: Sep 19, 1996.
- Full Report:
Pursuant to a congressional request, GAO assessed the Centers for Disease Control and Prevention's (CDC) National Immunization Survey (NIS), focusing on: (1) survey costs; (2) survey methods; and (3) use in identifying groups of children in need of more timely immunization.
GAO found that: (1) CDC designed NIS for monitoring state progress in achieving child immunization objectives, comparing coverage rates across states, and awarding incentive funds; (2) CDC estimates and contractor invoices indicate that NIS costs for fiscal year (FY) 1995, including extraordinary expenses incurred when 1994 survey participants were reinterviewed, were about $13 million; (3) although CDC anticipates that survey costs will decrease in the future, it has requested $16 million for NIS administration for FY 1997; (4) the two-phase survey methodology, which gathers information by telephone from households and immunization providers, excludes households that lack a telephone, may not accurately represent the overall population, and is limited by response accuracy; (5) NIS has not achieved sufficient precision in its survey estimates to detect modest changes that occur in most coverage levels; (6) CDC considers the identification of groups of children in need of more timely immunization as a state rather than a federal responsibility and has not designed and does not use NIS to make such identifications; and (7) interviews with state officials indicate that NIS is not useful in helping states to diagnose problems in immunization activities, target efforts, or design interventions.
Matter for Congressional Consideration
Status: Closed - Implemented
Comments: Congress did not act on this recommendation. CDC has taken steps to augment the statistical expertise applied to the survey.
Matter: Congress may wish to reconsider NIS benefits relative to its cost. At a minimum, Congress may want to ensure that the CDC appropriation reflects a more accurate estimate of the survey's cost.